The use of double metal cyanide complex ("DMC") catalysts in the preparation of polyols having low ethylenic unsaturation is well-established in the art, as illustrated, for example, by U.S. Pat. No. 3,829,505. The polyols prepared using these catalysts can be fabricated to have a higher molecular weight and/or a lower amount of end group unsaturation than can be prepared using commonly-employed potassium hydroxide ("KOH") catalysts . The '505 patent discloses that these high molecular weight polyol products are suitably reacted with polyisocyanates to prepare rigid or flexible polyurethanes.
Unfortunately, it has now been found by the present inventors that, when utilizing polyols other than ethylene oxide ("EO")-capped polyols, the reactivity of the polyols made with DMC catalysts is less than otherwise might be desired in the subsequent reaction of the polyol with an isocyanate to produce a polyurethane.
A solution to this problem of less-than-desired reactivity would be highly desired by the DMC-catalyzed polyol manufacturing community. The present invention provides one solution to this problem.